32 research outputs found
Primate iPS cells as tools for evolutionary analyses
Induced pluripotent stem cells (iPSCs) are regarded as a central tool to understand human biology in health and disease. Similarly, iPSCs from non-human primates should be a central tool to understand human evolution, in particular for assessing the conservation of regulatory networks in iPSC models. Here, we have generated human, gorilla, bonobo and cynomolgus monkey iPSCs and assess their usefulness in such a framework. We show that these cells are well comparable in their differentiation potential and are generally similar to human, cynomolgus and rhesus monkey embryonic stem cells (ESCs). RNA sequencing reveals that expression differences among clones, individuals and stem cell type are all of very similar magnitude within a species. In contrast, expression differences between closely related primate species are three times larger and most genes show significant expression differences among the analyzed species. However, pseudogenes differ more than twice as much, suggesting that evolution of expression levels in primate stem cells is rapid, but constrained. These patterns in pluripotent stem cells are comparable to those found in other tissues except testis. Hence, primate iPSCs reveal insights into general primate gene expression evolution and should provide a rich source to identify conserved and species-specific gene expression patterns for cellular phenotypes
Structural conservation of an ancient tRNA sensor in eukaryotic glutaminyl-tRNA synthetase
In all organisms, aminoacyl tRNA synthetases covalently attach amino acids to their cognate tRNAs. Many eukaryotic tRNA synthetases have acquired appended domains, whose origin, structure and function are poorly understood. The N-terminal appended domain (NTD) of glutaminyl-tRNA synthetase (GlnRS) is intriguing since GlnRS is primarily a eukaryotic enzyme, whereas in other kingdoms Gln-tRNAGln is primarily synthesized by first forming Glu-tRNAGln, followed by conversion to Gln-tRNAGln by a tRNA-dependent amidotransferase. We report a functional and structural analysis of the NTD of Saccharomyces cerevisiae GlnRS, Gln4. Yeast mutants lacking the NTD exhibit growth defects, and Gln4 lacking the NTD has reduced complementarity for tRNAGln and glutamine. The 187-amino acid Gln4 NTD, crystallized and solved at 2.3āĆ
resolution, consists of two subdomains, each exhibiting an extraordinary structural resemblance to adjacent tRNA specificity-determining domains in the GatB subunit of the GatCAB amidotransferase, which forms Gln-tRNAGln. These subdomains are connected by an apparent hinge comprised of conserved residues. Mutation of these amino acids produces Gln4 variants with reduced affinity for tRNAGln, consistent with a hinge-closing mechanism proposed for GatB recognition of tRNA. Our results suggest a possible origin and function of the NTD that would link the phylogenetically diverse mechanisms of Gln-tRNAGln synthesis
Distance Learning Practices in Military Training and Education
21st Annual Conference on Distance Teaching and Learnin
Laboratory monitoring or measurement of direct oral anticoagulants (DOACs): Advantages, limitations and future challenges
The Direct Oral Anticoagulants (DOACs) represent a new generation of antithrombotic agents, providing direct inhibition of either thrombin (factor IIa; FIIa) or activated factor X (FXa). Around the globe, their use is progressively rising, as these new agents replace the historical anticoagulants (heparin and vitamin K antagonists including warfarin) for various clinical conditions in medical practice. Other acronyms used to designate DOACs include TSOAC (target specific oral anticoagulants) and NOAC (novel; or non-vitamin K antagonist oral anticoagulants). Currently available DOACS include dabigatran (FIIa inhibitor), along with rivaroxaban, apixaban, edoxaban and betrixaban (FXa inhibitors)
Australian and New Zealand approach to diagnosis and management of vaccine_induced immune thrombosis and thrombocytopenia
Intravenous iron vs blood for acute post-partum anaemia (IIBAPPA): a prospective randomised trial
Abstract Background Acute post-partum anaemia can be associated with significant morbidity including a predisposition for postnatal depression. Lack of clear practice guidelines means a number of women are treated with multiple blood transfusions. Intravenous iron has the potential to limit the need for multiple blood transfusions but its role in the post-partum setting is unclear. Methods/design IIBAPPA is a multi-centre randomised non-inferiority trial. Women with a primary post-partum haemorrhage (PPH) >1000Ā mL and resultant haemoglobin (Hb) 5.5-8.0Ā g/dL after resuscitation with ongoing symptomatic anaemia who are otherwise stable (no active bleeding) are eligible to participate. Patients with sepsis or conditions necessitating rapid Hb restoration are excluded. Eligible participants are randomised to receive a blood transfusion or a single dose of intravenous iron polymaltose calculated using the Ganzoni formula. Primary outcome measures include Hb, Ferritin and C-Reactive Protein levels on Day 7. Secondary outcomes evaluate (i) Hb, Ferritin and CRP levels on Day 14, 28, (ii) anaemia symptoms on Day 0, 7, 14 and 28 using structured health related quality of life questionnaires, (iii) treatment safety by assessing adverse reactions and infection endpoints and (iv) the quantitative impact of anaemia on breast feeding quality using a hospital designed questionnaire. Discussion If equivalence in Hb and ferritin levels, symptom scores and safety endpoints is demonstrated, intravenous iron may become the preferred treatment for women with acute post-partum anaemia to minimise transfusion reactions and costs. Trial registration Australian and New Zealand Clinical Trials Registry: ACTRN12615001370594 on 16th December, 2015 (prospective approval)
Natural history of hypercoagulability in patients undergoing coronary revascularization and effect of preoperative myocardial infarction
Objectives: The balance between hyper- and hypocoagulable states is critical after coronary artery surgery both with (coronary artery bypass grafting [CABG]) and without (off-pump coronary artery bypass [OPCAB]) cardiopulmonary bypass to prevent thrombotic or bleeding complications. We aimed to quantify novel parameters of coagulation, fibrinolysis, and overall hemostasi
Characterization of the hypercoagulable state following severe orthopedic trauma
BACKGROUND: Acute traumatic coagulopathy develops in seriously injured patients, which is followed by a paradoxical hypercoagulable state. The hypercoagulable state contributes to venous thromboembolism, and yet, there are no sensitive tests available to detect it. The aim of this study was to characterize the hypercoagulable state caused by major orthopedic trauma using the overall hemostatic potential (OHP) assay. METHODS: Major orthopedic trauma patients admitted during a 7-month period in 2012 were included in the study. Blood samples were drawn 1 hour before surgery, then 1, 7, 24 hours and 3, 5, 10, and 42 days postoperatively. The assay parameters were determined and analyzed according to injury severity (polytrauma or nonpolytrauma), type of surgical intervention, and shock status. Values were compared with 20 healthy controls. RESULTS: Forty-one consecutive patients were enrolled (age, 41.5 Ā± 2.7 years; 70% male; Injury Severity Score [ISS], 21.5 Ā± 2.1). Hypercoagulability based on OHP was present in the preoperative sample compared with the controls (OHP, 13.8 Ā± 1.4 U vs. 8.1 Ā± 0.5 U; <i>p</i> = 0.020) and then further elevated after surgery (1 hour postoperative, 17.8 Ā± 2.0 U vs. preoperative, 13.8 Ā± 1.4 U, <i>p</i> = 0.008). Polytrauma patients were more hypercoagulable than nonpolytrauma at the preoperative sample time (17.7 Ā± 2.6 U vs. 10.7 Ā± 1.2 U, <i>p</i> = 0.040) and postoperative period (24.3 Ā± 3.4 U vs. 11.9 Ā± 1.4 U, <i>p</i> = 0.006). The OHP for patients undergoing open pelvic surgery (28.3 Ā± 3.0 U) was higher than both intramedullary nailing (16.2 Ā± 2.0 U) and percutaneous pelvic surgery (17.0 Ā± 1.7 U) on Day 5 (<i>p</i> < 0.05). Patients demonstrated a higher OHP than controls did at all time points, except at 6 weeks (patients, 10.8 Ā± 1.7 U vs. controls, 8.1 Ā± 0.5 U; <i>p</i> = 0.400). CONCLUSION: The OHP assay detected the hypercoagulable state following major orthopedic trauma and surgical intervention, which was present for 10 days postoperatively. The extent of hypercoagulability could be associated with polytrauma and the type of surgical intervention; however, further studies are needed to confirm this